Useful tools

This is a small library of schematic parts. Reference numbers and values are queried and added as attributes:

Autocad schematic parts library (zip file 192K)

This is a slightly larger library of parts for PCB layout, mostly surface mount. It includes 3D shapes. Reference numbers and values are in attribute form:

Autocad PCB parts library (zip file 1.6M)

This is an Excel spread sheet that calculates values for two pole and three pole butterworth bandpass filters as well as selected chebychev filters. Using the solve function it optimises for standard component values. Uneven terminations are allowed using Norton's transformer method. The three pole filters have an intermediate impedence that gives more flexability for component values.

Filter spreadsheet (zip file 23K)

Back to the home page